Meetings 2011-08-18

Report on (RSB Use in) MORSE (Florian)

  • MORSE
    • Bullet physics engine
    • Python scripting
  • RSB-related Issue
    • Blender depends on Python3.2
    • We will make a rsb-python for porting work
  • Demo in one/two week(s)
    • RSB + Blender
    • RSB + MORSE

RSBag (Michael, Jan)

Current State

  • C++ Implementation
    • Can write TIDELog files
    • Partial read support
    • Client interface and RSB integration are not finished
    • No commandline tools
  • Common Lisp
    • Can read and write
    • Basic RSB integration (only event payloads; no meta-data yet)
    • Commandline tools
      • bag-record: almost done
      • bag-play: not done yet

RSB Channel <-> TIDELog Mapping

Alternatives:
  • One TIDELog channel for each user specified scope (current behavior)
    • Leads to mixed types in channel entries
  • One TIDELog channel for each RSB scope (without sub-scopes)
    • Channels for sub-scopes are dynamically allocated when events arrive
  • One TIDELog channel for each (RSB scope, payload type) combination

Should the TIDELog file format include per-entry meta-data?

  • Problem
    • Replaying RSB events requires more than just one timestamp and the payload to be stored: event meta-data and some transport information has to be serialized and stored as well
  • Pros
    • Slightly reduced lock-in since only a TIDELog library and an IDL of the payload are required (vs. knowledge of the event serialization mechanism)
    • More beautiful (in Lars' words ;)
  • Cons
    • Where to stop? Why not an arbitrary amount of blobs for each entry
    • Requires modification of TIDELog file format
    • Reading data from a log requires knowledge of the payload data format anyway; having to know the structure of the entire serialized event is not that much worse
  • Decision
    • We will store serialized events in the respective entry's blob
    • We should still talk to Ingo about this issue

Initial Set of Tools and supported Use-cases

  • No implementation in other languages (or at least not now)
  • Supported use-cases
    • Recording one or more scopes (with filtering)
    • Replay of events to one or more scopes (with filtering)

rsb-gstreamer (Johannes, Jan)

Current State

  • One GStreamer plugin libgstrsb.so
    • Uses .rst.ImageMessage and .rst.SoundMessage
    • Two elements
      • rsbvideosrc
      • rsbaudiosrc
  • Timestamps are a problem

Cause Vectors (Johannes)

postponed